Moving snow off of open ground, streets, sidewalks and parking lots is an age-old problem in less temperate climates where significant snowfall is anticipated during colder periods of the year. For instance, in many parts of Canada and in many northern states in the United States, significant snowfall can be expected during the late fall and early-to-mid winter months, and again in the late winter and even, at times, early spring.
Clearing freshly fallen snow from open ground, parking lots, driveways, sidewalks and roadways, whether these surfaces are paved or not, is a task common to all of these areas that is generally required to make these surfaces safe and passable, both initially and over time if the snow begins to build up after multiple snowfalls. If the snow is allowed to accumulate over a period of weeks, the snow eventually makes the use of these surfaces for both pedestrian and vehicular travel difficult, if not treacherous. Therefore, many devices have been designed and manufactured to remove freshly fallen and accumulated snow from such surfaces.
Municipalities generally use large vehicles with enormous snow plows to clear paved roadways used by the public, and county and state government public works and transportation departments in these areas also generally have a fleet of these kinds of vehicles to clear snow from roadways and from large parking lots on county-owned or state-owned properties.
The purchase and use of such a vehicle by individuals, however, who have a need to move or remove accumulated snow in smaller areas, such as driveways and privately owned parking areas, is less feasible. First of all, the larger vehicles are expensive to purchase and maintain and are, in some cases, dedicated solely to the removal of accumulated snow. It will be appreciated that it would not be cost effective for an individual to purchase, house and maintain such a vehicle for just removing snow from driveways and smaller parking lots during a limited period of the year. Furthermore, these vehicles are difficult to operate and often require significant training or experience operating such vehicles.
For this reason, many inventors have designed and manufactured adjustable snow plows that can be attached to pickup trucks and other vehicles for a period of time during the year when snow removal is required. In this way, the vehicles can be used for other purposes during periods when snow removal is not required.
Many of the snow plows attached to these vehicles, however, are large and heavy and are not easily attached and removed from the vehicles. A number of snow plows have been invented that attempt to address these problems. For instance, Kowalczyk (U.S. Pat. No. 4,944,104) discloses a detachable snow plow assembly that is pivotally attached to a common passenger vehicle. In one embodiment of the invention, the snow plow includes rollers secured within channels attached to mounting uprights to allow the plow blade to ride up and down when the blade comes into contact with irregularities in the surface. The plow blade can also pivot forward along with the mounting uprights in certain embodiments when the vehicle is moving backward allowing the plow blade to pivot forward over the ground. In other disclosures, such as the snow plow assembly disclosed by Rosenberg (U.S. Pat. No. 5,136,795), a trip mechanism is disclosed which allows the lower part of the plow blade to pivot backward when the plow blade comes into contact with relatively immovable objects and the trip mechanism is actuated. Rosenberg also discloses a rubber scraper at the bottom of the plow blade which is secured between two metal plates and oriented at an angle rearward of a vertical orientation. Rubber scrapers are also disclosed on older snow plows, such as the snow plow mold board disclosed by C. H. Wagner (U.S. Pat. No. 3,477,149), which discloses a resilient scraping blade made of rubber. This is a common feature in many snow plows, allowing the rubber scraper to contact the ground and provide a somewhat more forgiving surface with which to contact the ground when the plow is used to remove accumulated snow, but the rubber scraper is generally accompanied by a metal backing.
Although each of these inventions has its own advantages, none of them are easy to attach to or remove from the vehicle. These snow plows also tend to be heavy and cumbersome, and at least somewhat unsightly if one is required, for practical reasons, to keep it attached to the vehicle 24/7 for a period of several months during the snow season.
The present invention provides a more cost effective and attractive snow plow for removing smaller amounts of accumulated snow from driveways and small-to-medium sized parking lots where one individual may wish to use his or her vehicle to remove snow during a relatively limited period of time, while still having use of the vehicle available for other purposes, not involving snow removal, when the snow plow must either be removed from the vehicle and/or placed in a suitable position for non-snow removing transit.
In addition, the prior art snow plows are generally so heavy that they will not ride up when they are on open ground, for instance, but will tear up the ground and remove grass and other plant things often just because of the sheer weight of the plow as it passes along the ground surface. Also, the prior art snow plows are often virtually impossible for a single person to handle, because of the weight associated with these plows; and plows that appear to be relatively light weight, such as the snow plow described by Knutson et al. (U.S. Pat. No. 6,240,658), generally have multiple attachment points and do not appear to be highly effective, durable or marketable.
The present invention provides solutions for these and other problems associated with the prior art devices for removing accumulated snow and methods used to accomplish the same.